As Delhi’s air quality drops to ‘severe+’ for the first time this season, the Air Quality Management Commission (AQIM) on Sunday decided to invoke phase IV of the Air Quality Plan. graduated response action (GRAP), which will come into effect from 8 a.m. Monday.

“The AQI of Delhi was recorded at 441 (Severe) at 4:00 p.m. today and has gradually increased and has already reached the Severe+ category, as the AQI recorded 447, 452 and 457 at 5:00 p.m. and 6:00 p.m. and 7:00 p.m., respectively,” said CAQM, the Centre’s panel on air quality in Delhi-NCR.